Means for orienting tools in bore holes



Nov. 10, 1942. T. E. MCMAHAN 2,301,307

MEANS FOR ORIENTING TOOLS IN A BORE HOLE Filed J n. 14, 1942 PatentedNov. 10, 1942 mmfs roa onmm'mo 'rooLs IN BORE noms Thomas EmmettMcMahan, Long Beach, Calif., assignor to- Richiield Oil Corporation, Los

Anzeles,

Calm, a corporation of Delaware Application January 14, 1942, Serial No.426,690

2 Claims. (CI. 255=1.6)

This invention relates to a device for determining the relations of adeflecting tool, bit, corebarrel or the like to a known azimuth in abore hole. This invention may be used in conjunction with any of thewell known methodsof directional survey recording in which case theresults obtained by this invention, coupled with the results of suchdirectional survey enable the operator to determine accurately thedeviation of the deflecting tool or whipstock, core-barrel, bit or othersuitable tool from a known azimuth. In many cases, owever, it isunnecessary to determine the deviation of the tool from a fixed or knownazimuth and a determination of the amount of deviation of the tool froma vertical plane passing through the axis of the bore hole issuflicient, in which case the results obtained need not be coupled withthose of any directional survey.

Though it has heretofore been proposed to derive the data sought by thisinvention by means of clinonieters inserted in the bore hole, suchreadings have been costly and employ oomphcated and often fragileequipment, such as acid bottles. Inaddition, prior devices in this arthave required the opening and disassembling of complicated devices andthe use of specially designed equipment and specially trained personnelto enable their results to be accuratelyread or intelligentlyinterpreted.

It is accordingly one object of this invention to provide a device ofthe type described which is economical, simple, sturdy, and which iseasily but positively operated and accurately read by the ordinaryoperating personnel of a drilling r g;

It is another object of this invention to provide a device of the classdescribed in whlch the two markings necessary for thedesired data arepresented upon a common impression block'and .in the same orsubstantially the same horizontal plane, in order, to facilitatereading.

It is another object of this invention to position the marking elementsof the device permanently in the drill string so that the only elementwhich must be removed from the well-for reading and returned forsuccessive operations is a simple impression block, suitably mounted,thus avoiding the insertion and removal from the bore hole ofcomplicated costly and delicate clinometers.

It is another object of this invention to provide amethod of orientingtools in a bore hole in which the data desired is obtained upon a 55single marking element which is adapted to be inserted in a compass cardand adjusted to give a direct readingof the deviation of the tool fromthe known direction of the bore hole.

Other objects and advantages appear hereinafter.

In its broadest aspects this invention consists in means for obtainingupon a single marking member. two marks or impressions, one supplied bya 'flxed member and indicating the horizontal position of the tool andtheother supplied by a ball free to move under the.force of gravity intoa marking position indicating the deviation of the toolfrom a verticalline. With these two marks or impressions upon a common marking memberthe operator can, upon inspection, determine the deviation of the toolfrom the previously determined direction of the bore hole and suitableshifting of the deflecting tool, if such is being utilized, may be madeto drill the well in any desired direction,

In the accompanying drawing:

Fig. 1 is a cross sectional elevation the invention in place in a well.

Fig. 2 is a plan view of a compass card employed with' my invention withthe impression block inserted therein.

Fig. 3 is a section taken upon the line 3-3 of Referring moreparticularly tofthe drawing, I have illustrated a length of drill pipeand tool joint I, connected by a rotary substitute 5 to a bit H. Adeflecting tool or whipstock I I is removably secured to the rotarysubstitute 5 by means of a bolt or shear pin Ill.

Mounted within the rotary substitute 5 is a striker 6 having a scribe orpoint 'I projecting into the opening I3 therein. A race 9 is positionedwithin the rotary substitute 5 and directly below the striker 6. A ball8 is freely contained in said race 9 and projects a small portion intothe opening IS in the striker 6.

showing A sinker bar 2 containing a lead or soft metal impression block3, retained therein by means of retaining member 4, is shown hung'in thedrill string by means of cable or rods ll.

The operation of the device is as follows: With the tools made up asshown-in Figure 1 and with the scribe or point I in known fixed posilionrelative to the face of the whipstock II, the string is lowered to apredetermined position.

When the string comes to rest the ball 8, mov

ing under the force of gravity, will run inzth race 9 to the low side ofthe tool, occasioned by the deviation of the bore hole. The. sinker bar2, containing the impression block 3, is then run The sinker bar andimpression block are then I removed from the drill string andtheimpression block 3 may be placed in a compass card l5, havingindicated thereon, as at IS, the direction of the bore hole, aspreviously determined by directional survey. The imprint l1, made byball 8, is placed 180 from the direction of the bore hole l6 and thenotch It! made by the scribe I will immediately indicate in degrees uponthe compass card IS the direction of the tool or whipstock with respectto the bore hole.

In the event that the readings thus obtained indicate an undesirablepositioning of the tool, the tool may be shifted, as by rotation of thedrill string, and the re-orientation checked by rerunning the sinker barand impression block for further orientation. In this manner the tool orwhipstock can be accurately positioned asv desired prior to shearing ofthe pin I0.

While the particular forms of the invention herein described are welladapted to carry out the objects of the invention, it is to beunderstood that various modifications and changes may be made withoutdeparting from the principles of the invention, and the inventionincludes all. such modifications and changes as come within the scope ofthe appended :claims.

2. In a device for orientingtools in a bore hole, the combination of adrill string, a pair of From the foregoing it will be apparent that I Ihave provided novel means and method for orienting production tools andthe like in a bore hole which are simple, economical, sturdy and noteasily destructible and which also provide for simple and accuratereading of the data secured.

marking elements permanently mounted in said drill string adjacent thetool to be oriented, one of said marking elements having a fixedposition relative to saidtool, the other of said marking elements beingfree to roll to thelower side of said drill string, 'and an impressionelement adapted to be lowered into said drill string for contact withsaid marking elements to secure a record of the position of said markingelements, said record lying in substantially a single horizontal plane.

THOMAS ,EMMETT McMAHAN.

